Abstract:

A new technique for making ferrous sulfate water purifying agent from pyrite cinder and titanium white waste acid has been studied.The process includes acid leaching，purification，reduction,filtration,freezing crystallization,and vacuum drying.The research focuses on the effect of acid leaching condition on leaching rate and the purification process on product quality. The result shows that the optimal conditions to make the leaching rate of iron reach 90% are as follows,40% of the sulfuric acid leaching solution is prepared with 98% of H2SO4 and 20% of titanium white waste acid,liquid-solid mass ratio is 4∶1,leaching time is 60 min.Ferrous sulfate and calcium oxide can be used for treating the arsenic-containing wastewater emitted from sulfuric acid plants.Thus,the effluent with As is less than 0.15 mg/L and achieves standard discharge.The process realizes the comprehensive utilization of pyrite cinder and titanium white waste acid.The product can be used for water treatment,and conforms to the cleaning requirements.

Key words: pyrite, ferrous sulfate, water purifying agent

摘要：

以硫铁矿烧渣和钛白废酸为原料，经酸浸、除杂、还原制得精制硫酸亚铁溶液，再经过滤、冷冻结晶、真空干燥制备了硫酸亚铁净水剂。考察了酸浸条件对浸出率的影响以及净化过程对浸出率、产品质量的影响，结果表明：采用98%H2SO4和20%的钛白废酸配制成40%的硫酸浸取液，控制液固质量比为4∶1，浸出时间为60 min，可使铁浸出率达到90%；用制备的硫酸亚铁和石灰处理硫酸厂的含砷废水，出水中As<0.15 mg/L，可实现达标排放。该工艺综合利用了硫铁矿烧渣和钛白废酸，产品可用于废水治理，符合清洁生产的要求。

关键词: 硫铁矿, 硫酸亚铁, 净水剂